Safety-guard for rotary grinding-machines



A. F. HOWE.. SAFETY GUARD FoR ROTARY GRINDING MACHINES.

APPLICATION FILED DE02?, 1918.

Patented sept. 7,1920.

'f Q i 9/////////// APPLICATION FILED DEC.27 I9I8.

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UNITED s'rATs PATENT vol-u-ucr..

ANDREW r. Howie, or GRANITE CITY, ILLINoIs, AssIGNon, BY MEsNE ASSIGNMENTS, To Howl: SAFETY APPLIANCE COMPANY, F GRANITE CITY, ILLINOIS, A conronA.

yZIIIION 0F ILLINOIS.

SAFETY-GUARD FOR ROTARY GRIDING-MACHINES.

Specification of Letters Patent.

Patented sept. 7, 1920.

Application led December 27, 1918. Serial No. 268,523.

following is a specification, reference being had to the accompanying drawings, forming a part thereof.

vThis invention relates generally to safety devices and, more particularly, to certain new and useful improvements in safety guards for emery wheels and other rotary grinding machines. v

Shop practice, in either formative, corrective, or finishing processes, generally employs a high speed rotary grindingwheel, and to expedite the work and as steps are and construction and whose connectingup of installation may be readily accomplished, which, though relatively light in weight, will efficiently not only arrest flying particles of the wheel, but also withstand the strains incident to, and catch and retain the broken pieces of, a bursting or explod- 1ng wheel, and which may be easily and convenlently adjusted relatively to the wheel to compensate for wheel reductions due to 'wear or material loss and thereby afford at of form, construction, arrangement, andcomblnatlon of parts herelnafter described' made, as the art advances, toward perfection and afterwardpointed out in the claims.

of cementing the abrasive material and per- In the accompanying drawings, fecting the bearings or mounts of the wheel, Figure l is a fragmental elevational view the tendency is to increase the speed of roof a two-wheel grinding-machine equipped tation of the wheel, which y now often with safety-guards constructed in accordreaches ve to seven thousand revolutions ance with and embodying my invention;

a minute. Fig. 2i's a transverse sectional view taken S0 I n work, particles of the wheel, which is approximately on the line 2-2, Fig. 1-;

usually of emery or other suitable abrasive, Fig. 3 is a fragmental end elevational are constantly being torn out and removed view of the machine illustrated in Fig. l, and, under the centrifugal force developed portions of the wheel-guard being shown in under the high speed l of y'rotation of the, section; 85

wheel, areimpelled or thrown outwardly from the wheelwith such force as to be a continuous source of annoyance and even danger to the operator, and it is not at all uncommon for a wheel, under its high speed of rotation, to burst orl explode and pieces thereof be thrown outwardly with such great force as to cause serious injury not only to the operator, but also to workmen and objects working or standing nearby.

Numerous contrivances have been devised as simple arresters for the impelled particles of emery or other abrasive, without regard for the arrest and retention of iiying pieces due to bursting ofthe wheel; and other'more or less cumbersome devices havey been developed to arrest and retain the broken iiying particles of an exploding wheel, but allsuch devices have been found, so far as I am aware, most inefficient. 'p

The objects of my presentinvention are yto provide a rotary wheel-guard which `is of relatively `light weight and compact in form Fig. 8 is a cross-sectional view of thel guard-stand taken approximately onthe line 8-8, Fig. 6.

Referring to the drawings, in which like reference characters refer to like parts throughout the several views, and having reference now more particularly to Figs. l,

2, and 3, my new safety-guard is illustrated in connection with a standard grindingmachine of double type comprising a base 1, a head 2, spaced shaftpillows 3-3, ashaft 4 mounted for rotation on the pillows 3 -3, a pulley 5 fixed on the shaft 4 intermediate the pillows y3 for belt connection with suitable power, and emery .or other rotary grinding wheels 6 6 mounted on the shaft 4 to rotate therewith. Such construction generally obtains in all grindin machines and is modified only in number o grindingwheels from a single wheel to more than two, as shown. Projecting laterally from the head 2, are rigid supports 7-7, upon which are mounted suitable tool-rests 8, as best seen in Figs. 2 and 3, but y,which I have omitted in Fig. 1 to permit a clearer illustration of other features. Each support 7 is slotted, as at 9, whereby its supported toolrest 8 may be conveniently adjusted relatively to the particular adjacent grindingwheel, as may be necessary or required in the work.

For conveniently supportin a respective guard upon the machine, provide a bracket 10 of substantially L-shape, one and the longer arm of the bracket being adapted to rest horizontally upon a support 7 and the other or shorter arm of the bracket extending upwardly and approximately vertically adjacent the wheel. As seen in Fi 1, where two of such, brackets are emplo e, the horizontal arm of one bracket is o set, as at 11, within its len h, so that it may neatly overlie the end o the horizontal arm of the other bracket; in other particulars the two brackets are identical in form an construction. Within the length of each horizontal arm of each bracket, is a longitudinal slot 12 which intersects the slot 9 of its support 7 and through which intersecting slots 12 and 9 a bolt 13 is extended, whereby the bracket may be facilely adjusted to selectively position its vertical arm with respect to the wheel, whose special relations With the supports and machine-head vary in different makes of machines. Each bracket is also provided longi'tudinally in its horizontal arm with an elongated slot, as at 14, through which slots 14 a bolt 15 may be extended to adjustably fasten together and lend rigidity to thel two brackets; obviously, with a machine having only one wheel, the slot 14 may be omitted or, if necessary or desired, the horizontal arm of the bracket may bereduced in length accordingly. The vertical arm of each bracket is also provided longitudinally, as seen especially in Fig. 2, with a pair of spaced parallel slots v16--1t, for purposes shortly appearing;

The guard proper comprises a lower half or sectlon A and an upper half or section B, each section being of hood shapeand both sect-ions being preferably of light sheet steel or other suitable metallic material. Lower section A consists of an arched rim or wall 17 substantially semi-circular in Sha'lp'in side elevation, and side walls 18-18 whose outer margins are correspondingly semicircular in shape and which are preferably welded or otherwise suitably united at their side outer margins to the o osite side edges of the rim or wall 17. pper section B similarly consists of anrarched rim or wall 19 and side walls 20-20, upper section B, however, being cut awayor reduced at its forward end to provide a suitable grindingspace in the finished guard for the work. The side walls 18 and 2O 'of the lower and u'pper sections A and B, respectively, are arcuately cut away at their inner margins as shown, rto accommodate the shaft 4 transversely of the guard and also-to permit adjustable shifting of the guard to operatively accommodate grinding-wheels of different diameter, as more fully hereinafter appears. At the rear of the guard, the rims or walls 17 and 19 of the lower and upper sections A Aand B, respectively, are elongated preferably integrally to provide cooperating hinge-members adapted to accommodate a pin or bolt 21 for pivotally fastening the sections A and B together, whereby the sections A and B may be relatively swung to.

facilitate the placement of'the guard over and around, or removal of the guard from over and around, a grindi1 wheel, and whereby also upper section justably swung away from lower section A to vary the width of thelgrinding-space at the front of the guard as may be required or. desired for the work being done.

22 indicates a fastening or securing for the guard. This plate 22 hasFpre erablj7 the shape or form best seen in igs. 2 and 4 and has fixed thereto intermediate its ends a pair of transverselyv disposed bolts 23-23 which are adapted to fit the slots 16-16 of the vertical arm of the su'pporting bracket 10. When its bolts 23 are extended through the slots 16 and fixed to the bracket, as by the nuts 24, the plate 22 forms or provides a rigid, non-rocking connection between the guard and bracket, such connection being adapted for adjustment as may be required to 'compensate for non-uniformity in vertical spacing. between thel wheel-shaft and tool-support in the various makes or types of grinding-machines. At its forward end, plate 22 is substantially longitudinally slotted, as at 25, to adjustably receive a fastening-bolt 26 fixed to, and projecting transversely from, the inner side wall 18 of the lower section A of the guard. At its rear end, the plate 22 is provided with a second slot, as at 27, adapted to adjustably receive one end of the hinge-pintle or bolt 21. The bolts 26 and 21 with their nuts thus provide a rigid connection between the guard as a whole and the plate 22, which connection is also adapted for adjustment 4to compensate forv wheel wear, said connection permitting may be adplate convenient shifting of the guard as a whole relatively to the plate 22 andthe inclosed wheel, so.that the guard may at all times be properly related to the wheel and as the 5 wheel is worn and reduced diametrically, brought nearer to the wheel at itsgrinding space where the work is brought .to -the wheel.

Pivotally fastened at its lower end to the 4, is an arcual arm 28 provided within its length with a corresponding arcual slot, as at 29, adapted to adjustably it and accomodate -a bolt 30 threaded into a side wall 20 of upper sectionlB. By means of the arm 28 and its described connection with the u per guard-section B, the section B may e releasably locked in any selected position to the plate 22 and also locked in any selected adjustably swung :position relatively to the lower guard-sectlon A.

For arresting sparks and particles flying from the wheel, I provide an arrester which is substantially in the'form ofa shield comprising a mam wall 31 having the Vshape best seen in Fig. 3, and side walls orears 32--32. This shield is disposed upon the upper guard-section B atl its forward or free end, as shown, and is pivotally fastened adjustably at its walls 32 to the side walls 20 of the said guard-section, the shield being carried upon the guard-section with its main wall 31 disposed at such an an le to the forward edge of the rim 19 of t e guard-section as to `stop and deflect inwardly vaway from the operator any fiying wheelsparks or particles. Thel shield being pivoted adjustably, as'described, upon the upper guard-section, it may be convenientl swingably adjusted relatively to the guar and fastened at selective angles upon the guard-section B so as to properly perform its function as the position of the guardsection B is changed or shifted relatively tothe inclosed wheel. The rim 17 oflower guard-section A is provided with an aperture, as at 33, forming an outlet from `the guard for the arrested sparks and particles..

Disposed upon the outer side wall 18 of the lower guard-sectionA, is a plate 34 provided with a slot, as at 35, in which a plurality of fastening-bolts 36 projected through said guard-wall 18 are adapted to fit for adjustably securing the plate to the guard.- Extending from the plate 34, preferably as a rigid integral extension thereof, is a cage 37'adapted to surround and guard the projecting end of the shaft 4.

In use'or operation, and first in installing tion B is swungl outwardly away from lower section A, the guard then placed in inclosing position upon the wheel, and the bolts 23 of itssecuring plate 22 then fastened to the vertical arm of the supporting bracket plate 22, as seen particularly in Figs. 2 and a guard over and upon a'wheel, upper sec- .10, the guard as a whole being adjusted, by

means of the `bolts 26 and 21 and coperating slots 25 and 27, approximately concentric with the wheel and its shaft 4. rIhe upper section B is thenswingably adjusted relatively to lower guard-section A as may be required in regulating the grinding-space at'the forward part of the guard and then locked selectively in such position by means of the arm 28 and its fastening bolt 3Q, the arrester being correspondingly adjuSted, as before described, relatively to the upper guard-section B. The plate 34 and its shaft-cage 37 are then fastened upon the guard, with cage 37 correspondingly concentric with, and inclosing the outer or free end of, the wheel-shaft 4. lVith the guard in such operative position, it will be evident that the. wheel and its shaft are substantially fully inclosed, with resulting safety to the operator, the guard and its arrester serving not only to prevent injury to the operator by flying sparks, particles, and the like, but the guard itself servin eliciently to' arrest and retain, and there y preventv injury to adjacent persons or objects by, the

outwardly impelled parts of an exploding lduced through wear, the slots 26 and 21 permit a ready shifting of the guard as a whole relatively to the inclosed wheel and the relatively ixed plate 22 to bring the grindingspace of the guard into-convenient worlring osition to the reduced wheel, as indicate by the dot-and-dash lines in F 1g. 2. And since such adjustment or shifting of the guard would obviously decenter the cage 37 .relatively to thel shaft, and since the cage 37 should be operatively approximately concentric with shaft 4 at all times, I provide the -plate 34 with the slot 35, before Adescribed, which correspondingly permits ready adjustment of the lcage 37 relatively tothe shaft, and for such purpose I pro-V vide an extra bolt-hole, as at 38, in the lower guard-section A to accommodate one of the cage-securing bolts 36 in any required ex- .treme adjustment of the cage. On any such lower guard-section A, as may be required.

and conveniently locked in such adjusted position, the arrester also being conveniently adjusted relatively to the reduced wheel as may be required on such shifting of the guard as a whole or on the adjustment of upper guard-section B only.

y In some instances, it may be desirable to support the guard' independently of the machine; hence I provide for such purpose a stand such as shown in Figs. 4, 5, and 6, which includes a bracket, taking the place of 'the described machine-brackets, comprising a base 39, rising vertically from and upon opposite sides of which are ears 40 and 41 disposed somewhat obliquely to each other, as best seen in Fig. 4, the ear 40 corresponding to the described vertical arm of the machine bracket and being correspondingly slotted to adj ustably receive the bolts 23, and the ear 41 being slotted or apertured, as at 42, to receive one end of the guard-pintle 21. Vith such bracket, the guard may be bodily moved or shifted for purposes of adjustment to the wheel in the same manner as has been described in connection with the machine brackets. Depjending from base 39 is a preferably non-circular stem 43, and by preference the base 39, ears 4() and 41, and stem 43 are formed as an integral unit. The stand proper, used in connection with the bracket just described, comprises a column 44 having supporting feet 45, which may be fixed to the floor near the wheel-stand or machine base or frame, the column 44 being longitudinally cored to receive the post 43 of the bracket, which bracket may be held in altitudinal adjusted positions relatively tothe column by means of one or more set-screws or the like 46 seated in the column, as shown, to engage the stem 43.

I am aware that minor changes in the form, construction, arrangement, and combination of the several parts of my new safety-guard may be made and substituted for those herein shown and described without departing from the nature and principle of my invention.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. A grinding-wheel safety-guard comprising a pair of hood-shaped sections cooperating to inclose the Wheel, in combination with means for supporting the guard 'as a whole around the wheel, said means including a separate plate having connection with a side wallof one of the sections.

2. A grinding-wheel safety-guard comprising a pair of`hood-shaped sections cooperating to inclose the wheel, in combination with means for adjustably supporting the guard as a whole around the wheel, said means including a separate plate having an adjustable connection with a side wall of one of the sections. f

3. A grinding-wheel safety-guard comprising a pair of hood-shaped sections and a pin hingedly connecting the sections together to inclose the wheel, in combination with means for supporting the guard as a whole around the wheel, said means including a separate plate having connection with the pin and with one of the sections.

4. A grinding-wheel safety-guard comprising'a pair ofhood-shaped sectionsfand a pin hingedly connecting the sections together to inclose the wheel, in combination slot to one of the with means for adjustably supporting the guard as a whole around the wheel, said means including a separate plate provided with slots, the plate having connection at said slots with the pin and with one of the sections.

5. A grinding-wheel safety-guard comprising a pair of hood-shaped sections'cooperating to inclose the wheel, in combination with means for ad'ustably supporting the guard around the W eel, said means including a bracket, and a separate plate fastened to the bracket, the plate being provided with slots and having adjustable connection at its slots with the guard.

6. A grinding-wheel safety-guard comprising a pair of cooperating hood-shaped connected sections adapted for operatively inclosing the guard, in combination with supporting means aording adjustments of the guard to inclose the wheel, said means including a bracket, and a plate fastened to the guard and adapted for adjustable engagement with the bracket.

7. A grinding-wheel safety-guard including a pair of hood-shaped sections hingedly connected to inclose the wheel, in combina- Y tion with a supporting plate fastened to one of the sections, and an arm having connection with the plate and with the other section for locking said other section against hinged movement relatively to the rst section.

8. A grinding-wheel safetyuard including a pair of hood-shaped' sections hingedly connected to inclose the wheel, in combination with a supporting plate fastened to one of the sections, and an arm having pivoted connection with the plate and adjustable connection with the other section for adjustably locking said other section against hinged movement relatively to the first section.

9. A grinding-wheel safety-guard comprising, in combination, a pair of coperating hood-shaped connected sections adapted for operatively inclosing the wheel, means for supporting the guard adjustably around the wheel, whereby the guard may be bodily shifted relatively to the inclosed wheel, and a shaft-end cage mounted adjustably upon the guard, whereby said cage may be adjustably shifted relatively to the shaft-end on adjustments of the guard relatively to the i inclosed wheel.

10. A grinding-wheel safety-guard comprising, 1n combination, a pair of hoodshaped sections cooperating to inclose the wheel, means for supporting the guard adjustably around the wheel, whereby the guard may be bodily shifted relatively to the inclosed wheel, and a shaft-end cage having a slotted extension adjustably fastened at its uard-sections, whereby said cage may be s ifted relatively to the shaft-end on adjustments of the guard rela.- tively to the inclosed wheel.

ing a pair of hood-shaped sections and a pin hingedy connecting the sections to inclose the Wheel, a plate having connection With one of the sections and With the pin, and a pair of spaced brackets on the support, the 15 plate having engagement with one of the brackets andthe pin having engagement with the other bracket.

In testimony whereof, I have signed my name to this specification.

ANDREW F. HOVE. 

